System for monitoring foreign particles, process processing apparatus and method of electronic commerce

ABSTRACT

A foreign matter monitoring system comprises: a production management system which manages the processing of workpieces in a manufacture line; foreign matter monitors mounted as on-machine equipment in plural process processing apparatuses of the manufacture line, said foreign matter monitors each having an optical head containing a detecting optical system for irradiating a workpiece with light and a detecting optical system for receiving reflected and scattered light from the workpiece and converting the received light to a detection image signal and an A/D converter for converting the detection image signal, which is obtained through conversion by the detecting optical system, to a detection digital image signal; and a base system having a control unit for acquiring control information, a buffer memory for storing said detection digital image signal which is acquired from each foreign matter monitor, a database storing inspection recipes each associated with a foreign matter monitor and an image signal processing unit used for, based on a detection digital image signal associated with a foreign matter monitor and acquired from the buffer memory, judging whether foreign matter and other defects are present on a workpiece according to an inspection recipe which is selected for the corresponding foreign matter monitor based on control information from the control unit.

BACKGROUND OF THE INVENTION

The present invention relates to a system for monitoring foreign matter(foreign particles) where its base system collectively receives andprocesses foreign matter detection signals from foreign mattermonitoring optical heads mounted in many process processing apparatuses(many process processing apparatuses) forming a manufacture line ofsemiconductors or the like, a process processing apparatus and anelectronic transaction method (a method of electronic commerce) usingthe system for monitoring foreign matter.

There are known conventional techniques concerning foreign mattermonitoring systems as disclosed in Japanese Patent Laid-Open Nos.5-218163 (corresponding to U.S. Pat. No. 5,463,459) (Prior Art 1),6-258239 (Prior Art 2), 8-250385 (corresponding to U.S. application.Ser. No. 08/617,270) (Prior Art 3), 8-250569 (corresponding to U.S.application. Ser. No. 08/617,270) (Prior Art 4).

In Prior Arts 1 and 2, an inline foreign matter monitor system isdescribed. In this case, compact foreign matter monitors are set up inthe inlets/outlets of process processing apparatuses or in transportareas between process processing apparatuses in a volume productionsemiconductor manufacture process line and a foreign matter controlsystem takes in foreign matter data from the compact foreign mattermonitors to provide foreign matter control on a single wafer basis. InPrior Arts 3 and 4, an on-machine foreign matter monitor system isdescribed. In this system, a process processing apparatus has a foreignmatter monitor mounted therein to measure foreign matters sticking toworks before and after they are processed therein so that foreignmatters sticking to works are under control on an each lot or work basisand, based on the result of measurement, it is determined whether workssupplied into the process processing apparatus should be stopped or not.

Technique disclosed in Japanese Patent Laid-Open No. 8-145900 (Prior Art5) is known as a conventional technique for compact foreign mattermonitors. According to Prior Art 5, compact foreign matter monitors areplaced where they are accessible by the arms of robots which are fixedbetween a vacuum process room and a loader and between a vacuum processroom and an unloader. In addition, a vacuum process apparatus isdescribed in Japanese Patent Laid-Open No. 5-259259 (Prior Art 6). Avacuum process apparatus according to this prior art has a load lockroom to relay a workpiece, a process room to process a workpiece, aninspection room having a foreign matter monitor installed therein and aplatform having transport means to transfer a workpiece among the loadlock room, process room and inspection room.

In Japanese Patent Laid-Open No. 6-275688 (Prior Art 7), failureanalysis technique is described. According to this prior art forsemiconductor wafers and the like, a foreign matter inspectionapparatus, an appearance inspection apparatus and a probing inspectionapparatus are connected to an appearance failure analysis apparatus viaeach analysis station and a product design support system and a datainput terminal are connected to the appearance failure analysisapparatus. To clarify a causal relationship, the apparatus failureanalysis apparatus compares the fail bit data acquired from the probinginspection apparatus with the appearance defect information acquiredfrom the appearance inspection apparatus.

SUMMARY OF THE INVENTION

Recent semiconductor chips, as represented by system LSIs, contain agreat number of functional circuit blocks formed by very fine circuitpatterns and they are becoming expensive more and more. Further,semiconductor wafers having arrays of these chips are becoming largerand more expensive. To improve the yield from a semiconductor devicemanufacture process line, it is therefore very important to find adusting source as early as possible (with a limited number of wafersinfluence) if any in the manufacture line in order to prevent thedusting from causing mass failure.

In addition, each semiconductor wafer goes through so many manufactureprocesses (including such common manufacture processes as photo process,film deposition process, etching process and CMP process) until it iscompleted. On the other hand, a major cause of bad semiconductor wafersis foreign matters which occur in individual process machines (etching,sputtering, CVD, exposure and other processing apparatus) and stick ontowafers therein., Basically, foreign matters do not stick tosemiconductor wafers while they are carried between process machinessince they are accommodated in cassettes which provides clean ambienceto semiconductor wafers. Therefore, on-machine foreign-matter monitorsare needed to detect foreign matters which stick to semiconductor wafersin individual process processing apparatuses as described in Prior Arts3 and 4.

However, although a foreign matter monitor system according to PriorArts 3 and 4 comprises compact and inexpensive foreign matter monitorsmounted in a great number of process processing apparatuses whichconstitutes a semiconductor manufacture line, its system configurationis not given sufficient consideration as part of the semiconductormanufacture line.

It is a first object of the present invention to provide a system formonitoring foreign matter (foreign particles) which comprises compactand inexpensive foreign matter monitors mounted in a great number ofmain process processing apparatuses constituting a manufacture line ofsemiconductors or the like and is optimized comprehensively as part-ofthe manufacture line.

It is a second object of the present invention to provide a processprocessing apparatus optimized to install a compact foreign mattermonitor.

It is a third object of the present invention to provide an electronictransaction method (a method of electronic commerce) using a foreignmatter monitor system.

According to an aspect of the present invention, there is provided asystem for monitoring foreign matter comprising: a manufacture linehaving plural process processing apparatuses; a production managementsystem which manages the processing of workpieces in the manufactureline; foreign matter monitors mounted as on-machine equipment in saidplural process processing apparatuses, said foreign matter monitors eachhaving: an optical head containing a detecting optical system forirradiating a workpiece with light and a detecting optical system forreceiving reflected and scattered light from the workpiece andconverting the received light to a detection image signal; and an A/Dconverter for converting the detection image signal, which is obtainedthrough conversion by the detecting optical system, to a detectiondigital image signal; and a base system having: a control unit foracquiring control information including information identifying eachforeign matter monitor, process processing information and workpieceinformation, the process processing information and the workpieceinformation being acquired from the production management system; abuffer memory for storing said detection digital image signal, which isacquired from each foreign matter monitor, in association with thecorresponding foreign matter monitor; a database storing inspectionrecipes each associated with a foreign matter monitor; and an imagesignal processing unit used for, based on a detection digital imagesignal associated with a foreign matter monitor and acquired from thebuffer memory, judging whether foreign matter and other defects arepresent on a workpiece according to an inspection recipe which isselected for the corresponding foreign matter monitor based on controlinformation from the control unit.

According to an embodiment of the present invention, there is provided aforeign matter monitoring system as described above and characterized inthat each of said main plural process processing apparatuses comprises:a process room to process workpieces; a cassette room where a cassettecontaining a workpiece is carried in and out; and a platform providingclean ambience to the workpiece for transportation between the processroom and the cassette room.

According to an embodiment of the present invention, there is provided aforeign matter monitoring system as described above and characterized inthat an optical head for the foreign matter monitor is set up in saidplatform.

According to an embodiment of the present invention, there is provided aforeign matter monitoring system as described above and characterized inthat each of said main plural process processing apparatuses comprises:a process room to process workpieces; a cassette room where a cassettecontaining a workpiece is carried in and out; a platform providing cleanambience to the workpiece for transportation between the process roomand the cassette room; and a small clean environment room.

According to an embodiment of the present invention, there is provided aforeign matter monitoring system as described above and characterized inthat an optical head for the foreign matter monitor is set up in saidsmall clean environment room and said clean ambience is kept clean toclass 20 or better.

According to an embodiment of the present invention, there is provided aforeign matter monitoring system as described above and characterized inthat said image signal processing unit in said base system is configuredso as to prepare a defect distribution map over a workpiece for eachforeign matter monitor, said base system further comprises a dataanalysis processing unit which performs failure analysis by comparingthe defect occurrence situation of a workpiece, judged by said imagesignal processing unit, with failure analysis reference data and resultsof failure analysis by said data analysis processing unit are displayedon an input/output terminal.

According to an embodiment of the present invention, there is provided aforeign matter monitoring system as described above and characterized inthat the control unit in said base system has a capability of preparinginspection recipes associated respectively with foreign matter monitors.

According to an aspect of the present invention, there is provided aprocess processing apparatus comprising: a platform which is evacuatedand provided with a transport robot set up therein; plural processchambers each of which is placed around the platform and has a gatewhich is opened and closed for various processing when a workpiece iscarried in or out through the gate by the transportation robot; a relayroom which is connected to the platform and has a gate which is openedand closed; a cassette room in which plural cassette each accommodatingplural workpieces are placed; and a small clean environment room whichprovides class 20 or better clean ambience for connection between therelay room and the cassette room and has a foreign matter monitoringoptical head, the head including a detecting optical system forirradiating a workpiece with light and a detecting optical system forreceiving reflected and scattered light from the workpiece andconverting the received light to a detection image signal.

According to an aspect of the present invention, there is provided aprocess processing apparatus group comprising: plural process processingapparatuses each having a cassette room in which a cassetteaccommodating plural workpieces is placed, a process room to processworkpieces carried in and out via a gate which is opened and closed, anda small clean environment room which has a transport robot carrying aworkpiece between the cassette room and the process room and is keptclean at almost atmospheric pressure, wherein the plural processprocessing apparatuses are placed around the travel path of an automatedguided vehicle; a foreign matter monitoring optical head containing adetecting optical system for irradiating a workpiece with light and adetecting optical system for receiving reflected and scattered lightfrom the workpiece and converting the received light to a detectionimage signal is set up in each small clean environment room for adesired process processing apparatus; and an automated guided vehicle isused to transfer a cassette into and from the cassette room of eachprocess processing apparatus.

According to an aspect of the present invention, there is provided anelectronic transaction method (a method of electronic commerce), whereinthe inspection equipment manufacturer which manufactures foreign mattermonitors using a foreign matter monitoring system demands payment via acommunication network to a chip device manufacturer for an economiceffect by an increased yield which is brought about as a result ofanti-failure countermeasures taken to an abnormal process processingapparatus located based on defect occurrence information acquired fromthe base system.

As mentioned above, according to-the present invention, it is possibleto realize a foreign matter monitoring system optimized for the whole ofa manufacture line of semiconductors or the like, which can mountcompact foreign matter monitors in clean ambience in main processprocessing apparatuses installed in the manufacture line and can use abase system to collectively process the digital image signals acquiredfrom these many compact foreign matter monitors.

According to the present invention, it is also possible to realize aprocess processing apparatus in which a compact foreign matter monitoris set up optimally.

According to the present invention, it is possible to implement anelectronic transaction method (a method of electronic commerce) using aforeign matter monitoring system.

While the invention has been described in its preferred embodiments, itis to be understood that the words which have been used are words ofdescription rather than limitation and that changes within the purviewof the appended claims may be made without departing from the true scopeand spirit of the invention in its broader aspects.

BRIEF DESCRIPTION OF THE INVENTION

Other objects and advantages of the invention will become apparent fromthe following description of embodiments with reference to theaccompanying drawings in which:

FIG. 1 shows the general configuration of an embodiment of a foreignmatter monitoring system according to the present invention;

FIG. 2 shows an embodiment in which a foreign matter monitoring systemaccording to the present invention is applied to a device manufactureprocess line;

FIG. 3 shows an embodiment in which a foreign matter monitoring systemaccording to the present invention is applied to among factories;

FIG. 4 is a front view of a first embodiment of a compact foreign mattermonitor set up in each process operation machine (each processprocessing apparatus) according to the present invention;

FIG. 5 is a top view of the embodiment shown in FIG. 4;

FIG. 6 is a front view of a second embodiment of a compact foreignmatter monitor set up in each process. processing apparatus according tothe present invention;

FIG. 7 is a top view of the embodiment shown in FIG. 6;

FIG. 8 is a front view of a third embodiment of a compact foreign mattermonitor set up in each process processing apparatus according to thepresent invention;

FIG. 9 a shows a case in which the whole surface of a wafer is inspectedat a time by a compact foreign matter monitor and FIG. 9 b shows a casein which a wafer is partially inspected with a reduced pixel size;

FIGS. 10 a and 10 b show top and front views of a batch processing typeprocess processing apparatus in which compact foreign matter monitorsaccording to the present invention is set up, respectively;

FIG. 11 shows a plan view of a single-wafer multi-chamber type processprocessing apparatus (1) in which compact foreign matter monitorsaccording to the present invention is set up;

FIG. 12 shows a plan view of a process processing apparatus in whichcompact foreign matter monitors according to the present invention areset up in a small clean environment room which is connected to aplatform;

FIG. 13 shows a plan view of a single-wafer continuous type processprocessing apparatus in which compact foreign matter monitors accordingto the present invention are set up;

FIG. 14 shows a top view of a single-wafer multi-chamber type processprocessing apparatus (2) in which compact foreign matter monitorsaccording to the present invention is set up;

FIG. 15 shows a process processing apparatus in which compact foreignmatter monitors according to the present invention are set up in a smallclean environment room which is larger than that of FIG. 12;

FIG. 16 shows a process processing apparatus in which compact foreignmatter monitors according to the present invention are set up in a smallclean environment room which is still larger than that of FIG. 15;

FIG. 17 shows a plan view of a system comprising many process processingapparatuses according to the present invention, each of which has aprocess chamber, a clean small environment room as a platform with acompact foreign matter monitor set up therein, and a cassette room andis placed along the transport route of an automated guided vehicle(AGV);

FIG. 18 is a diagram for explaining the contents of a database in a basesystem according to the present invention;

FIG. 19 is a diagram for explaining functions of a control unit in abase system according to the present invention;

FIG. 20 shows flows of processing done in a base system designed in sucha manner that operation of a control unit is triggered by data from anexternal system according to the present invention;

FIG. 21 shows flows of processing done in a base system in which acontrol unit is designed to access an external system according to thepresent invention;

FIG. 22 is a diagram for explaining the general configuration of a firstembodiment of an image signal processing unit in a base system accordingto the present invention;

FIG. 23 is a diagram for explaining the general configuration of asecond embodiment of an image signal processing unit in a base systemaccording to the present invention;

FIG. 24 is a diagram for explaining image processing in an image signalprocessing unit;

FIG. 25 is a diagram for explaining how a probable dusting source islocated by a data analysis processing unit in a base system according tothe present invention;

FIG. 26 is an example of failure analysis reference data;

FIG. 27 shows a screen which is displayed as a failure analysis resulton an input/output terminal;

FIG. 28 shows net foreign matter distributions obtained by compactforeign matter monitors set up respectively for chambers;

FIG. 29 shows how the number of foreign matters depends on respectiveparameters (pressure sensor value, temperature sensor value, gas flowrate and degree of vacuum);

FIG. 30 shows a screen indicating in detail how the number of foreignmatters detected in each process processing apparatus changed with time;

FIG. 31 shows a screen designed to cover more process processingapparatuses than in the screen of FIG. 30 and allow switching to adetailed format;

FIG. 32 shows a hardware configuration to implement an electronictransaction method using a foreign matter monitoring system according tothe present invention;

FIG. 33 is a diagram for explaining a basic sequence in an electronictransaction method (a method of electronic commerce) according to thepresent invention;

FIG. 34 is a diagram for explaining a first example of how to calculatethe amount of money to be paid for inspection in an electronictransaction method according to the present invention;

FIG. 35 is a diagram for explaining a second example of how to calculatethe amount of money to be paid for inspection in an electronictransaction method according to the present invention;

FIG. 36 is a diagram for explaining a third example of how to calculatethe amount of money to be paid for inspection in an electronictransaction method according to the present invention;

FIG. 37 is a diagram for explaining how payment is demanded to aproduction apparatus manufacturer in an electronic transaction methodaccording to the present invention;

FIG. 38 is a diagram for explaining how rating service is provided by arating company (for example, an inspection equipment manufacturer) in anelectronic transaction method according to the present invention;

FIG. 39 is a diagram for explaining how a production apparatusmanufacturer initiatively demands payment in an electronic transactionmethod according to the present invention; and

FIG. 40 is a diagram for explaining how a compact foreign matter monitor(optical head) is added in an electronic transaction method according tothe present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings, the embodiments of the present invention willbe described.

An on-machine foreign matter monitor system according to the presentinvention intends to find dusting in any process of a semiconductordevice manufacture line as early as possible so that the influence ofthe process dusting is limited to a minimum number of wafers withoutcausing a mass of failures and, as shown in FIG. 1 and FIG. 2, includescompact foreign matter monitors (optical heads) 10 a through 10 n and abase system 20. Each compact foreign matter monitor 10, whose hardwareconfiguration is minimized in order to save the cost price, is installedin one of process processing apparatuses (etching, sputtering, CVD,exposure and other processing apparatuses) Pa to Pm. The base system 20has: reception ports 241 a to 241 n which at least receive A/D-converteddigital image signals from the many compact foreign matter monitors 10 athrough 10 n; an image signal processing unit 210 which receives monitoridentification, inspection start and other signals and perform imagesignal processing in order to detect foreign matter (foreign particles)generated in any of the process processing apparatuses Pa through Pmplaced in the manufacture line; and a data analysis processing unit 220which, based on foreign matter detection signals obtained as the resultof the image signal processing, performs data analysis processing inorder to immediately judges whether and where abnormality has occurredand issue an instruction to stop the process processing apparatus Pjudged abnormal. The process processing apparatuses Pa through Pm wherethe compact foreign matter monitors 10 a through 10 m are respectivelyinstalled are the major one which are likely to generate foreign matter.In particular, a control unit 250 in the base system 20 is provided withan on/off monitor function in order to guarantee that a detection signalis incoming to the base system 20 from each compact foreign mattermonitor 10 since detection processing and analysis processing are notdone on the compact foreign matter monitor 10 side including theconveyance system arranged therein.

Then, how the above mentioned on-machine foreign matter monitor systemis applied to a semiconductor device manufacture process line by usingFIG. 2 will be described. Assume that the semiconductor devicemanufacture process line comprises a process A having process processingapparatuses Pa1 through Pa3 installed therein, a process B havingprocess processing apparatuses Pb1 through Pb3 and a process C havingprocess processing apparatuses Pc1 through Pc3. In each of these processprocessing apparatuses Pa1 through Pa3, Pb1 through Pb3 and Pc1 throughPc3, the compact foreign matter monitors (optical heads) 10 a 1 through10 a 3, 10 b 1 through 10 b 3 and 10 c 1 through 10 c 3 are respectivelymounted in clean ambience. The input and output of each of the manyoptical heads 10 in the respective processes A through C are connectedto the base system 20 via, for example, a network 12. In addition, theprocess processing apparatuses P in the respective processes A through Care connected to a production management system (a production controlsystem) 30 via, for example, the network 12 to perform productioncontrol. The base system 20, the production system 30, a measuringdevice group 40 having standalone type inspection devices (ordinaryforeign matter inspection units, appearance inspection units, etc.) andan electric inspection system 50 which tests the operation ofsemiconductor circuits are connected to the network 12. Accordingly, therespective digital image signals given identification codes areregularly incoming to the base system 20 via the network 12 andreception ports 241 a through 241 c from the corresponding compactforeign matter monitors (each having an optical head) 10a 1 through 10 c3 installed in the process processing apparatuses Pa1 through Pc3 andare stored in a buffer memory 240. Each digital image signal can be readout therefrom by the image signal processing unit 210 by use of thecorresponding identification code. The image signal processing unit 210detects foreign matter signals by performing image processingconsistently with a processing condition set to the compact foreignmatter monitor. Based on the detected foreign matter signals, the dataanalysis processing unit 230 performs data analysis processing in orderto create foreign matter distribution maps on an each wafer or lotbasis, judge immediately whether the process processing apparatus isabnormal and, if so, issue an instruction to stop the apparatus.

Although FIG. 2 shows a continuous line having a sequence of manufactureprocesses, the monitor system may also be a line dispersed in a factoryor process processing apparatuses of the same kind. Examples of acontinuous line include an etcher, CVD, coater, developer, etc. In thiscase, the base system 20 can perform foreign matter control more finelyso as to minimize the loss. If the monitor system is applied to afactory-wide manufacture line, the base system 20 can performcomprehensive foreign matter control. In addition, if the monitor systemis applied to process processing apparatuses of the same kind, the basesystem 20 can control the foreign matter differences among theapparatuses and find an abnormal process processing apparatus.

As shown in FIG. 3, the on-machine foreign matter monitor system canalso be applied to among factories. Factories S, T and U respectivelyhave process machine groups (process apparatus groups) Ps, Pt and Putherein, each of which comprises a great number of process processingapparatuses. Compact foreign matter monitor groups 10 s, 10 t and 10 u,mounted respectively in the machine groups, are connected tocommunication cable mains 62 s, 62 t and 62 u in the respectivefactories via communication cables 61 s, 61 t and 61 u. Productionmanagement systems (production control systems) 30 s, 30 t and 30 u arerespectively connected to the process processing apparatus groups(process operation machine groups) Ps, Pt and Pu via the communicationcable mains 62 s, 62 t and 62 u so as to provide management on an eachfactory basis. The communication cable mains 62 s, 62 t and 62 u in therespective factories are connected to a communication network 64 such asthe Internet via communication cables 63 s, 63 t and 64 t. Thecommunication network 60 is connected to a base system 20 located in,for example, an inspection equipment manufacturer. This allows the basesystem 20 to perform inter-factory foreign matter detection processingand data analysis to detect and stop abnormal process machines andtherefore put foreign matter occurrence under inter-factory control. Inaddition, this allows the base system 20 to provide such information asforeign matter occurrence in a specific factory to that factory togetherwith derived yield-related information.

Then, embodiments of a compact foreign matter monitor (having an opticalhead) 10 including a conveyance system will be described. Eachembodiment described below is mounted on a main process machine (a mainprocess apparatus), a part of a manufacture line constituting anon-machine foreign matter monitor system according to the presentinvention

As shown in FIG. 4, a first embodiment of a compact foreign mattermonitor 10 includes an optical unit (optical head) 100 a, a locatingsystem 130 a and a control device 135. The optical unit 100 a comprisesan illuminating optical system 110 a and a detecting optical system 120a. The illuminating optical system 110 a comprises: an illuminationlight source 111 consisting of a laser light source, etc.; an AO(Acousto-Optical) deflector 112 which deflects the illumination lightemitted from the illumination light source 111; and a condenser lens 113which condenses the deflected light from the AO deflector 112 toirradiate a wafer 1 at a large incident angle. The detecting opticalsystem 120 a comprises: an objective lens 121 to condense scattered,reflected light from the wafer 1; a focusing lens 122 to focus thecondensed reflected light from the objective lens 121; and an opticaldetector 123 which receives an optical image formed by the focusing lens122, converts it to an image signal, A/D-converts the signal and outputsthe resulting digital image signal 124. The locating system 130 acarries the wafer 1 mounted thereon. The control device 135 controls thelocating system 130 a, the AO deflector 112, starts and stops inspectionand controls the intensity of illumination from the illumination lightsource 111 as necessary. The structure of the compact foreign mattermonitor, including the control circuit, is simplified this manner so asto lower the cost price.

In the first embodiment, as shown in FIG. 5, an illumination spot 114condensed through the condenser lens 113 is deflected by the AOdeflector 112 to scan the wafer 1 in the scanning direction 115 of theillumination light while the wafer 1 is moved in the wafer conveyancedirection 131 by the locating system 130 a so that a specified area isscanned two-dimensionally. As a result, a digital image signal 124obtained from the specified area is given the identification code of thecompact foreign, matter monitor and output for transmission to areception port of the base system. This scanned area can be specified bythe process processing apparatus. In addition, in the case of the firstembodiment, the locating system 130 a has only to move in the waferconveyance direction 131. For example, it is possible to use a wafertransport robot carrying the wafer 1 between a loader or unloader (wafercassette) and a process room as described later. That is, the firstembodiment can be configured in such a manner that foreign matterdetection is done while the wafer 1 is on a hand of the wafer transportrobot. From each compact foreign matter monitor 10 to the base system20, at least a detection start signal is entered with its identificationcode via the reception port 241. In short, this is the minimum controlinformation which must be transferred (exchanged) between the controlunit 250 in the base system 20 and the control device 135 in the compactforeign matter monitor.

A second embodiment of the compact foreign matter monitor 10, as shownin FIG. 6, is applicable for foreign matter detection wherepre-alignment is done with a rotary stage. Since a pre-alignment opticalsystem (not shown) exists where pre-alignment is done, either an opticalunit (optical head) 100 b must be arranged so as not to interfere withthe pre-alignment optical system or the pre-alignment optical system andoptical unit (optical head) 100 b must be able to advance and retreat(movable) so as not to interfere with each other. Accordingly, thesecond embodiment has a mechanism for advancing and retreating theoptical unit 100 b (an optical unit locating system 140 b forpositioning in the optical unit movement direction 141). A locatingsystem 130 b has a rotary wafer mount stage which rotates forpre-alignment with the orientation flat. In the case of the secondembodiment, the optical unit (optical head) 100 b is configured in thesame manner as the first embodiment except that the illuminating opticalsystem 110 b can use a condenser lens 112″, instead of an AO deflector.In addition, in order to prevent interference with the pre-alignmentoptical system (not shown), the optical axis of the detecting opticalsystem 120 b is deviated from the perpendicular direction to such adegree that the regularly reflected light does not go incident on theiris of the objective lens 121. Accordingly, in the second embodiment, apre-specified area on the wafer is scanned in a spiral or arc fashion byan illumination spot 114 as shown in FIG. 7. As a result, a digitalimage signal 124 obtained from the specified area is output from theoptical detector 123. From each compact foreign matter monitor 10 to thebase system 20, at least a detection start signal is entered with itsidentification code via a reception port 241. In short, this is theminimum control information which must be transferred (exchanged)between the control unit 250 in the base system 20 and the controldevice 135 in the compact foreign matter monitor.

A third embodiment of the compact foreign matter monitor 10 assumes thatalmost the whole surface of a wafer 1 mounted on a stationary stage 130c having no conveyance system is inspected at a time as shown in FIG. 8.The third embodiment has an optical unit (optical unit) 100 c comprisingan illuminating optical system 110 c and a detecting optical system 120c. The illuminating optical system 110 c comprises an illumination lightsource 111′, a magnifying optical system 113′ by which the luminous fluxfrom the illumination light source 111′ is magnified so as to irradiatethe whole surface of a wafer and a half mirror 115 by which themagnified luminous flux from the magnifying optical system 113′ isreflected so as to irradiate the whole surface of the wafer. Thedetecting optical system 120 c comprises a telecentric optical system121′ and 122′ and a TV camera (detector) 123′ having an A/D conversioncircuit. Accordingly, in the third embodiment, a digital image signal124′ covering the whole surface of the wafer is obtained by the TVcamera 123′, with the signal 124′ having a field of view 145 a as shownin FIG. 9 a. To decrease the pixel size of the TV camera (detector)123′, i.e., raise the detection sensitivity, it is necessary topartially move the detector or telecentric optical system so that thefield of view 145 b for pickup is narrowed as shown in FIG. 9 b.

Then, how compact foreign matter monitors 10 are installed in a varietyof process processing apparatuses will be described with reference todrawings. FIGS. 10 a and 10 b show a part of a batch processing typeprocess processing apparatus (for LP-CVD (Low Pressure Chemical VaporDeposition), etc.) in which a compact foreign matter monitor 10 isinstalled. A batch processing type process processing apparatus 150comprises a cassette room 155, a preliminary treatment area 151, a batchtype process room 152 and a wafer transport robot 153. Wafers 1 areaccommodated in cassettes which are sealed to prevent penetration offoreign matter when they are carried into and out from the cassette room155 which exists in clean ambience. To and from the cassette room 155,the preliminary treatment area 151 and the batch type process room 152,the wafer transport robot 153 conveys wafers 1 through a platform 154.Since the platform 154 is kept clean to class 20 or better, thepossibility of foreign matter sticking to wafers is low. When a wafer istransferred between a cassette and the platform 154, the front gate ofthe cassette is opened and closed or it is opened and closed after anelevator along which the wafer is moved between the container and a slotis lifted down. Therefore, foreign matter may stick to wafers only inthe batch type process 152. Accordingly, the compact foreign mattermonitor 10 may be set up in an area where wafers are transferred by thewafer transport robot 153 to and from the platform 154, in an areabefore the gate of the batch type process room 152 or in the preliminarytreatment area 151. A locating system 130 a to locate the compactforeign matter monitor 10 can be implemented by using the action of thearm of the robot 153. If the preliminary treatment area 151 has a rotarystage, it may be used, too.

FIG. 11 shows a part of a single-wafer multi-chamber type processprocessing apparatus (for P-CVD, dry etching, sputtering, etc.) where acompact foreign matter monitor 10 is installed. This process processingapparatus 160 has a cassette room 164, five process chambers 161 athrough 161 e and a platform 162 provided with a wafer transport robot163. Similar to the above-mentioned one 155, the cassette room 164exists in clean ambience and stores a cassette accommodating a wafer. Ifthe cassette is 8 inches in size, it is called an standard mechanicalinterface. If the cassette is equal to or larger than 12 inches, it iscalled a front opening unified pod.

The compact foreign matter monitor 10 may be set up in an area wherewafers are transferred by the wafer transport robot 163 to and from theplatform 162, in a process chamber 161 c and around an process chamber161 a. If the compact foreign matter monitor 10 is set up around theprocess chamber 161 a, it is assumed that the side wall of the processchamber 161 a has a transparent window (not shown) through which a wafertherein can be observed by the compact foreign matter monitor 10.

In FIG. 12, compact foreign matter monitors 10 are set up in a smallclean environment connected to the wafer platform of a processprocessing apparatus. This small clean environment room 170 has a wafertransport robot 171 which passes wafers between the wafer relay room 165of the process processing apparatus 160′ and each of plural ports 175where cassettes are placed. In addition, the small clean environmentroom 170 has a pre-alignment section 172. Ambience in the small cleanenvironment room 170 is kept clean to class 20 or better (substantiallyclass 1) at around the atmospheric pressure. Needless to say, each ofthe plural ports 175 is a place into which a gate-closed hermeticcassette accommodating a wafer in its clean environment is carried fromexternal. The wafer transport robot 171 takes out a wafer into the cleanmini environment 170 from a gate-opened cassette placed in a desired oneof the plural ports 175 which are kept clean to class 20 or better.Then, the wafer transport robot 171 carries the wafer to thepre-alignment section 172 and mounts the wafer on its rotary stage. Inthe pre-alignment section 172, the wafer's orientation flat is opticallydetected and the rotary stage is rotated so as to direct the orientationflat to a certain direction. With this, pre-alignment is complete withthe orientation flat of the wafer mounted in the pre-alignment section172. Then, the wafer transport robot 171 lifts up the pre-aligned waferand mounts it on a stage in the wafer relay room 165. This wafer mountedon the stage in the wafer relay room 165 is brought into the respectiveprocess chambers 161 a through 161 e sequentially by a wafer transportrobot 163 installed in a platform 162. After processing is complete, thewafer is mounted on the stage in the wafer relay room 165. Then, thewafer transport robot 171 in the small clean environment room 170 takesout the wafer from the stage in the wafer relay room 165, puts it in therelevant cassette and closes its gate, making it possible to carry outthe sealed cassette into the external ambience (kept clean to class 1000to 10000 at atmospheric pressure).

As described above, if the small clean environment room 170 is included,the compact foreign matter monitor 10 may be set up in the rotarystage-used pre-alignment area 172 or within the operation range of thearm of the wafer transport robot 171 in the small clean environment room170

FIG. 13 shows a part of a single-wafer continuous type processprocessing apparatus (for atmospheric pressure CVD, washing, resistcoating, etc.) where the compact foreign matter monitor 10 is set up.The process processing apparatus 180 comprises: a process room 181having a resist coater; a process room 182 having an exposure system; aprocess room 183 having a development unit; a wafer transport belt 184to convey a wafer among these process rooms; and a wafer transport robot186 which takes out a wafer from a desired cassette room 185 into theprocess room 181 and carries the wafer processed in the process room 183into a desired cassette room 185. Since the inside of the processprocessing apparatus 180 is kept clean to class 20 or better(substantially 1) similar to the above-mentioned small clean environmentroom 170, foreign matter occurs mainly in the process rooms 181 through183. Therefore, the compact foreign matter monitor 10 is set up forbetween process rooms or a travel end of the wafer transport robot 186where ambience is kept clean to class 20 or better at around atmosphericpressure.

FIG. 14 shows a part of a single-wafer multi-chamber type processprocessing apparatus (for P-CVD, dry etching, sputtering, etc.) where acompact foreign matter monitor 10 is set up. This process processingapparatus 160′ has a relay room 165 between multi-chamber sets and onemulti-chamber set is provided with a plurality of cassette rooms 164.The compact foreign matter monitor 10 is set up in the platform 162 ofone multi-chamber set, in the relay room 165, where ambience is keptclean to class 20 or better, or in one process chamber 161 e belongingto the other multi-chamber set.

FIG. 15 shows where a compact foreign matter monitor 10 is set up in aprocess processing apparatus having a small clean environment room whichis equivalent to but longer than the one shown in FIG. 12. This processprocessing apparatus 185 has the long clean mini environment 170′ keptclean to class 20 or better and further includes process rooms 181through 184 (those shown in FIG. 13) placed along the mini environment170′. A plurality of wafer transport robots 171 are provided in theclean mini environment 170′. The compact foreign matter monitor 10 isset up in such a position as to be accessible by some wafer transportrobot 171 (or automated guided vehicle) in the clean mini environment170′.

FIG. 16 shows where a compact foreign matter monitor is set up in aprocess processing apparatus which has small clean environment room andprocess chamber pairs placed along the travel path of a wafer stage.This process processing apparatus 190 comprises a plurality of equipmentsets, each of which includes a process chamber 191 and a small cleanenvironment room 193, placed along the travel path 194 of the waferstage 195 and a wafer transfer robot 192 which transfers a wafer betweena cassette port 196 at an end of the machine and the travel path 194.Cassettes are also transferred between the cassette port 196 and acassette transport system (not shown) including a bay-to-bay automatedguide vehicle, etc. The compact foreign matter monitor 10 is to be setup over the travel path 194 along which the wafer stage 195 moves. Notonly the platforms 193 provided with the wafer transfer robot 192 butalso the travel path 194 are kept clean to class 20 or better by aircurtain or the like.

FIG. 17 shows where a compact foreign matter monitor is set up in aprocess processing apparatus which has small clean environment room,process chamber and cassette room sets placed along the travel path ofan automated guided vehicle. This process processing apparatus 190′comprises a plurality of equipment sets, each of which includes aprocess chamber 191, a small clean environment room 193 and a cassetteroom 164, placed along the travel path 198 of the automated guidedvehicle 197, and cassette ports 199 at an end of the machine. In eachsmall clean environment room 193, a wafer transport robot 192 totransfer a wafer and a compact foreign matter monitor 10 are set up. Allsmall clean environment rooms 193 and cassette rooms 164 which areconnected to the respective process chambers 191 are kept clean to class20 or better at atmospheric pressure. The automated guided vehicle 197transfers sealed cassettes between the cassette rooms 164 and thecassette ports which are kept clean to class 1000 to 10000.

It is preferable to add a small clean environment room 170, 193, whichis kept clean to class 20 or better, to a process processing apparatusand set up a compact foreign matter monitor 10 in the small cleanenvironment rooms 170, 193 as described above.

Then, embodiments of the base system 20 shown in FIG. 1 through FIG. 3will be described. As shown in FIG. 1, image data (digital imagesignals) 124 a through 124 n from compact foreign matter monitors 10 athrough 10 n enter the base system 20 via its reception ports 241 athrough 241 n and are stored together with the identification codes ofthe compact foreign matter monitors 10 a through 10 n in theirassociated addresses in the buffer memory 240. In addition, inspectionstart signals and the like from each of the compact foreign mattermonitors 10 a through 10 n enter the base system 20 via its receptionports 241 a through 241 n and are stored in the control unit 250.Needless to say, the control unit 250 may store identification codes andother various information, which are obtained from the compact foreignmatter monitors 10 a through 10 n, into the database 251. Identificationcodes may be given to either the compact foreign matter monitor side orthe reception port side.

Although using “identification codes” is assumed in the abovedescription as a method for identifying each of the many dataoriginators, that is, the compact foreign matter monitors 10 a through10 n, identification is also possible by assigning a differentcommunication data frequency to each compact foreign matter monitor(broadband communication). Such broadband communication allows highspeed data transmission by using an existing network. In addition, datafrom a plurality of compact foreign matter monitors can be transmittedusing one line of the network.

In addition, wafer flow information, such as the type of the product(wafer) being processed by the process processing apparatus P in whichthe compact foreign matter monitor is set up and the name of the process(including the lot number), and manufacture line information, such asthe name of the process processing apparatus (including the location ofthe compact foreign matter monitor), the name of the manufacturer of theprocess processing apparatus and the name of the factory ((a) waferprocess data, (b) wafer layout data, (c) data on the process processingapparatus and compact foreign matter monitor as listed in FIG. 18) arereceived by the control unit 250 from an external system such as aproduction management system 30 and stored in the database 251. Also inthe database 251, history data ((h) failure analysis reference data(foreign matter distribution data)) obtained for each compact foreignmatter monitor as a result of analysis by the data analysis unit 230 arestored in association with the above-mentioned corresponding wafer flowinformation (manufacture process information) and manufacture lineinformation. In addition, if the image signal processing unit 210 a isconfigured as shown in FIG. 22, (d) inspection reference image data(reference digital image signal), which is to be compared with the imagedata retrieved from the buffer memory 240, is prepared and stored in thedatabase 251. Alternatively, image data obtained from a foreignmatter-free wafer by a compact foreign matter monitor can also be usedas (d) inspection reference image data (reference digital image signal).

In summary, as listed in FIG. 18, (a) wafer process data, (b) in-waferlayout data, (c) data on the process processing apparatus and compactforeign matter monitor, (d) inspection reference image data, (e)inspection recipe data ((e-1) threshold for judgment, (e-2) quantity ofillumination light, (e-3) inspection area, (e-4) inspection method), (f)inspection result data, (g) defective area image data and (h) failureanalysis reference image data are stored in the database 251. Inparticular, of the inspection recipe data, (e-3) inspection area and(e-4) inspection method (relative positional coordinates of the opticalhead relative to the wafer by XY scan or rotary scan) are used forcoordinate translation from each foreign matter detection signal to thewafer being inspected.

In addition, the control unit 250 has the control functions listed inFIG. 19 ({circumflex over (1)} compact foreign matter monitor on/offcheck function, {circumflex over (2)} signal processing timing controlfunction, {circumflex over (3)} inspection recipe prepare function,{circumflex over (4)} identification code recognize function,{circumflex over (5)} inspection recipe select function, {circumflexover (6)} alarm output function and {circumflex over (7)} compactforeign matter monitor optical head maintenance management function,etc.).

Then, flows of processing which is triggered by data from an externalsystem (a compact foreign matter monitor as the case may be) will bedescribed with reference to FIG. 20. In the flows of processing in thebase system 20 shown in FIG. 20, the control unit 250 performs controlso as to immediately start inspection processing as described below ifinspection information is received from an external system. The buffermemory 240 is always storing digital image data from the compact foreignmatter monitors 10 a through 10 n (S201). The control unit 250 obtainsinspection information (process data, layout data, requirement data onthe process processing apparatus and compact foreign matter monitor forinspection, etc.) from an external system such as the productionmanagement system 30 and stores them in the database 251 (S202). Then,based on the obtained inspection information, the control unit 250selects an inspection recipe (reference image data for comparison,threshold for judgment, inspection area, quantity of illumination light,inspection method, etc.) (S203). Then, the control unit 250 obtains theidentification code of an optical head for which the inspection recipeis selected (S204) and, based on the obtained identification code,searches the buffer memory 240 for the corresponding information (S205).If no corresponding image data is found in Step 205, the control unit250 performs error processing (Step 206). Otherwise, the control unit250 issues an image transmission command and image processing command(S207). This error processing includes in AND OR some of the following:(I) waiting for a certain period of time and then retrying retrievalwith the identification code, (II) indicating on the input/outputterminal 260 that image data is absent, (III) logging the inspectionprocessing error (product type and process) and (IV) terminating theinspection processing without doing anything. Then, the control unit 250sets an image signal processing condition based on the selected recipe(S208) and the buffer memory 240 transmits the relevant image data tothe image signal processing unit 210 based on the image transmissioncommand (S209). The image signal processing unit 210 processes thereceived image data according to the set image signal processingcondition (S210) and, upon completion (S211), stores the signalprocessing result ((f) inspection result data and (g) defective areaimage data) in the database 251 (S212). After verifying that the signalprocessing is terminated (S214), the control unit 250 not only instructsthe data analysis unit 220 to perform data analysis processing (S214)and outputs the result to, for example, the input/output terminal 260for display thereon but also outputs analysis information and alarminformation to external systems such as the production management system30 and process processing apparatus P as necessary.

Then, with reference to FIG. 21, flows of processing done in the basesystem 20 where the control unit 20 is designed to access externalsystems will be described. In the flows of processing shown in FIG. 21,the control unit 250 controls an external system to search forinspection information when image data is stored in the buffer memory240. Of the flows of processing, steps S216 through S220 are differentfrom those in FIG. 20. In these steps, the control unit 250 firstlysearches the buffer memory (S216) to check if new image data is stored(S217) and, if present, identifies the corresponding process processingapparatus from the identification code (S218). The control unit 250obtains wafer information and other inspection information from externalsystems such as the production management system 30 according to theidentified process processing apparatus (S219) and, based on theobtained inspection information, selects an inspection recipe (S220).The subsequent flows of processing are same as those shown in FIG. 20.

The control unit 250 can automatically prepare inspection recipes. Basedon the mechanical data (quantity of illumination light, illuminationangle and angle of the detecting optical axis) obtained from therespective compact foreign matter monitors 10 with wafer type-basedreference image data (raw digital image signals), the control unit 250automatically prepares inspection recipes where inspection areas,judgment thresholds and others are specified. Judgment thresholds canalso be determined by a method described in Japanese Patent Laid-OpenNo. 2000-105203.

Then, embodiments of the image signal processing unit 210 will bedescribed with reference to FIG. 22, FIG. 23 and FIG. 24. Since theimage signal processing unit 210 must process great amounts of detectedimage data which are obtained from many compact foreign matter monitors10 a through 10 n and stored in the buffer memory 240, high speedprocessing is required. The image signal processing unit 210 may also bedesigned in such a manner that priority is given to process processingapparatuss which has a possibility of suffering a great amount offoreign matter when detection image data is incoming from many compactforeign matter monitors 10 a through 10 n.

In the case of an embodiment shown in FIG. 22, the image signalprocessing unit 210 a comprises a difference processing block 212, athreshold processing block 213 and a coordinate translation processingblock 214. As shown in FIG. 24, the difference processing block 212obtains a difference between reference image data 216 stored in thedatabase 251 and detection image data 217 obtained from each compactforeign matter monitor by using a synchronization signal 219 and outputsthe difference data 218. In the threshold processing block 213, thedifference data 218 output from the difference processing block 212 isbinarized to a foreign matter signal according to a judgment thresholdspecified in an inspection recipe which is selected from the database251 according to the wafer type, quantity of illumination light, etc. Inthe coordinate translation block 214, the coordinates of the foreignmatter signal detected by the threshold processing block 213 aretranslated into those in the coordinate system of the wafer underinspection according to the inspection area and inspection methodspecified in the inspection recipe selected from the database 251. Thesynchronization signal 219 is given to both data 216 and 217 which enterthe difference processing block 212 so that the difference between thereference image data 216 and detection image data 217 can be calculated.A coordinate of each detected foreign matter can be determined accordingto the number of pixels from the synchronization signal 219. As for theinspection area and inspection method, the relative positional relationbetween the optical head and wafer in each process processing apparatusmust be measured and stored in the database 251 in advance as inspectionrecipe data. Needless to say, the difference processing block 212 mayperform difference processing for an inspection area specified in theselected inspection recipe data. In this manner, the coordinatetranslation block 214 of the image signal processing unit 210 a providesforeign matter occurrence maps 231 a through 231 n for the respectivewafers under inspection by the compact foreign matter monitors 10 athrough 10 n.

In the case of an embodiment shown in FIG. 23, the image signalprocessing unit 210 b comprises: a delay memory 225 in which detectionimage data 217 from each of the compact foreign matter monitors 10 athrough 10 n is delayed by one repetitive pattern (one chip); adifference processing block 212; a threshold processing block 213; and acoordinate translation block 214. This embodiment is different from thatshown in FIG. 22 in that the reference image data (reference digitalimage signal) is obtained from the delay memory 225.

Then the data analysis processing unit 220 concretely will be described.In the data analysis processing unit 220, as shown in FIG. 25, foreignmatter and other defect inspection results 231 a through 231 n, whichare obtained from the image signal processing unit 210 in associationwith the respective compact foreign matter monitors 10 a through 10 n,are compared with foreign matter distribution data (sampled pastinspection results) which are failure analysis reference data stored inthe database 251. Then, the data analysis processing unit 220 analyzesthe results of comparison to locate probable dusting sources among theprocess processing apparatuses Pa through Pn. If a result of comparisonis abnormal, an alarm is not only displayed with a probable dustingsource on the input/output terminal 260 but also sent to the externalproduction management system 30 and the process processing apparatusjudged abnormal. The notified process processing apparatus immediatelystops its process operation so as not to generate defective wafers.

In the database 251, failure analysis reference data (foreign matterdistribution data) such as shown in FIG. 26 are prepared. For example,type A may be attributable to damage by a robot arm, type B to dustingin chamber Z and type C to dusting from a chuck.

FIG. 27 shows a result of analysis by the data analysis processing unit230. Indicated are defect distributions detected by the image signalprocessing unit 210 in wafers after or before manufacture process CCC isapplied to these wafers set in slots 1 through 5 in process processingapparatus AAA. The wafers belongs to product type BBB and lot No. DDD.As a result of analysis, an alarm 271 is output to indicate thatabnormal defects are found in a wafer set in slot 5 and they may beattributable to damage by a robot arm.

Shown in FIG. 28 are inspection results obtained from the image signalprocessing unit 210 and analysis results (net foreign matters) by dataanalysis processing unit 220 when compact foreign matter monitors 10 areset up respectively in a platform 162 for a cassette room 164, chamber A161 a and chamber B 161 b in a process processing apparatus. From thesenet foreign matter distributions, it is found that chamber A is dusting.

If the relations of the number of foreign matters per wafer with the gaspressure, supplied gas flow rate, temperature and degree of vacuum arestored as part of the failure analysis reference data in the database251 for each of process chambers 151, 161, 181 and 191 in a processprocessing apparatus which may generate foreign matters, it is possibleto find a probable cause of a large number of foreign matters accordingto the gas pressure, supplied gas flow rate, temperature and degree ofvacuum measured in chambers 151, 161, 181 and 191 while wafers werescanned. In FIG. 29, the measured gas pressure, temperature and degreeof vacuum are in the respective normal ranges and the large number offoreign matters are attributable to the gas flow rate.

FIG. 30 shows a screen displayed on the input/output terminal by thedata analysis processing unit 220. The number of foreign mattersdetected in one of every five wafers in each process processingapparatus is plotted at each inspection date. Accordingly, if the numberof foreign matters detected in one of every five wafers in a processprocessing apparatus becomes likely to exceed the foreign matter controlvalue, the data analysis processing unit 220 may notify of thissituation and issue an alarm to the process processing apparatus. Forexample, if the number of wafers having more foreign matters than theforeign matter control value (the number of out of control wafers) hasreached to 5, the data analysis processing unit 220 notifies of thissituation and issues an alarm to the process processing apparatus. Inthe case of a screen shown in FIG. 31, more process processingapparatuses are covered. Changes in the number of foreign mattersdetected per wafer in many process processing apparatuses arerespectively displayed on the input/output terminal 260 by the dataanalysis processing unit 220. This screen can indicate more abnormalprocess processing apparatuses in which the number of detected foreignmatters is going to exceed the control value.

In addition, if the correlation of the number of detected foreignmatters and the yield is stored as part of the failure analysisreference data in the database 251, it is possible to predict the totalyield of the manufacture line since the number of foreign mattersdetected in each process of the manufacture line can be grasped by thedata analysis processing unit 220. Anyway, the base system 20 obtainsyield information from the electric inspection system 50. In addition,information generated by offline inspection/analysis can be collected tothe base system 20 from the measuring device group 40.

When the base system 20 cannot be connected to an external system, theinput/output terminal 260 is used to input and output information.

Then an example of implementing electronic trade by using compactforeign matter monitors 10 as on-machine monitors according to thepresent invention as described so far will be described. Mountingcompact foreign matter monitors 10 in many process processingapparatuses as on-machine monitors makes the manufacture line veryexpensive. Therefore, compact foreign matter monitors 10 are leased to adevice manufacturer 500 or a production apparatus manufacturer 520 freeof charge or at a low rate. Since the base system 20 can always monitorthe manufacture line to check if foreign matters occur through compactforeign matter monitors 10 a through 10 n mounted in major processprocessing apparatuses. Pa through Pn constituting the manufacture line,it is possible to immediately take measures aimed at improving theyield.

FIG. 32 describes the general configuration of this embodiment. A basesystem 20 set up in a device manufacturer 500, an accounting system 610set up in an inspection equipment manufacturer 600 and a monitor system710 set up in a production apparatus manufacturer 700 are connected viaa communication network 800.

The device manufacturer 500 requests the inspection equipmentmanufacturer 600 to lease a compact foreign matter monitor 10 via thenetwork 800 and contracts with the inspection equipment manufacturer600. The device manufacturer 500 requests the manufacturer 700 of theprocess processing apparatus P to set up a compact foreign mattermonitor in the process processing apparatus P and contracts with theproduction apparatus manufacturer 700. The inspection equipmentmanufacturer 600 leases and sets up the compact foreign matter monitor10 for the device manufacturer 500. This results in compact foreignmatter monitors 10 a through 10 n mounted on process processingapparatuses Pa through Pn as on-machine monitors. After it is verifiedthrough inspection over a certain period that they are free fromabnormality, how to calculate the amount of payment for inspection isdetermined between the device manufacturer 500 and the inspectionequipment manufacturer 600. After this, the compact foreign mattermonitors 10 a through 10 n are put to regular use and the base system 20always monitors the manufacture line to check if foreign matters occurabnormally and performs feedback so that measures can be taken ifnecessary. As a result, the yield can be improved as an economic effectby inspection. Accordingly, the device manufacturer 500 pays money inthe accounting system 610 of the inspection equipment manufacturer 600for the economic effect (increase in the yield) by inspection.

Then, an example of a sequence in which the inspection equipmentmanufacturer 600 demands payment from the device manufacturer 500 willbe described with reference to FIG. 33. The accounting system 610 of theinspection equipment manufacturer 600 sends a foreign matter monitoroperation password to the base system 20 or production management system30 of the device manufacturer 500. As a result, the accounting system610 is notified by the base system 20 or production management system 30of the economic effect (increase in the yield) brought about byinspection and, based on this, demands payment for inspection over theterm of contract (one month or year). The device manufacturer 610 paysthe demanded amount of money in the accounting system 610 which in turnsends an updated password to the base system 20 or production managementsystem 30.

Then a first example of how to calculate the amount of money to be paidfor inspection will be described with reference to FIG. 34. Economiceffect E by foreign matter monitors is expressed by Equation (1) asbelow:E=m×ΔY×V×k  (1)where, m is the number of wafers processed in a low yield period, ΔY isa difference in the yield, V is the unit wafer price and k is acoefficient. For example, m equals (average dusting period inmanufacture apparatus A, regular foreign matter QC interval or time leftuntil the next regular QC)×(average number of wafers processed perhour). V equals (chip manufacture cost)×(number of chips yielded perwafer).

Then, a second example of how to calculate the amount of money to bepaid for inspection will be described with reference to FIG. 35. Inshort, a control foreign matter count is determined from a linearcorrelation between the number of detected foreign matters and the yieldjointly by the inspection equipment manufacturer 600 and devicemanufacturer 500. If the number of detected foreign matters, reported asan inspection result from the device manufacturer 500, exceeds thepredetermined control foreign matter count, the inspection equipmentmanufacturer 600 sends an alarm to the device manufacturer and demandspayment for instruction. Instead of the number of detected foreignmatters, the judgment may also be based on the number of foreign mattersbeyond a certain size, the density of foreign matters, the distributionof foreign matters or the like. Note that the yield-related data areobtained from the electric inspection system 50.

Then, a third example of how to calculate the amount of money to be paidfor inspection will be described with reference to FIG. 36. In the thirdexample, the amount of money to be paid for inspection is calculatedaccording to yield influence dY instead of the yield. Using yieldinfluence dY makes it possible to accurately estimate the influence offoreign matters in the pertinent process processing apparatus. Byrepresenting the yield of foreign matter present chips as Yp, the yieldof chips free from foreign mater as Yn, the ratio of foreign matterdetected chips to all chips as γ and the probability of a chip failingdue to foreign matter as F, yield influence dY is expressed by Equation(2) as below:dY=Yn×F×γ  (2)

-   -   where, Y=(Gn+Gp)/(Gn+Bn+Gp+Bp),    -   Yn=Gn/(Gn+Bn),    -   Yp=Gp/(Gp+Bp),    -   γ=(Gp+Bp)/(Gn+Bn+Gp+Bp) and    -   F=1−(Yp/Yn)

Then, an example of a sequence in which a production apparatusmanufacturer is demanded to pay for cost will be described. Theaccounting system 610 of an inspection equipment manufacturer 600 sendsa foreign monitor operation password to the base system 20 or productionmanagement system 30 of a device manufacturer 500. As a result, theaccounting system 610 collects dusting information about processprocessing apparatuses as inspection results from the base system 20 orproduction management system 30, and sends the dusting information aboutthe process processing apparatuses to the monitor system 710 of themanufacturer 700 of the process processing apparatuses. The monitorsystem 710 issue an alarm and notice to the base system 20 or productionmanagement system 30 of the device manufacturer 500 in order to notifyof countermeasures which must be taken to suppress dusting forpreventing mass failure and demands payment for this consultancy. Thedevice manufacturer 500 pays the demanded amount of money to theproduction apparatus manufacturer 700. The production apparatusmanufacturer 700 pays to the accounting system 610 of the inspectionequipment manufacturer 600 for the foreign matter monitoring cost. Theaccounting system 610 of the inspection equipment manufacturer 600 sendsan updated password to the base system 20 or production managementsystem 30 of the device manufacturer 500.

In this configuration, the production apparatus manufacturer 700 cansell dusting check-guaranteed production apparatus to the devicemanufacturer 500 and consequently can be paid for anti-dustingcountermeasures. The inspection equipment manufacturer 600 can also bepaid for the foreign matter monitoring cost. In addition, the devicemanufacturer 500 can use process processing apparatuses P withoutuneasiness since anti-dusting countermeasure service is guaranteed.

Then, an example of a sequence in which rating service is provided by arating company (inspection equipment manufacturer) will be describedwith reference to FIG. 38. Firstly, the rating company 650 pays to adevice manufacturer 500 for information collecting. Consequently, thedevice manufacturer 500 provides information, such as the number offoreign matters, density of defects and yield, to the rating company650. Then, a chip design company 900 pays to the rating company 600 foracquiring rating information about device manufacturers. Consequently,the rating company 600 encrypted rating information to the chip designcompany 900. Encryption intends to prevent the sent information frombeing misappropriated. As a result of this sequence, the device designmanufacturer 900 commissions a good device manufacturer to manufacture adesigned device and pays for the manufacture.

As described above, since the rating company 650 acquires highreliability information, such as the number of foreign matters andyield, from device manufacturers, and provides the information to thedevice design company 900, the device design company 900 can obtainchips manufactured according to a design from a device manufacturer atlow cost (in short TAT). The rating company 650 can take an intermediatemargin. If the inspection equipment manufacturer 600 serves as a ratingcompany 650, sale of its own equipment may be promoted. In addition, thedevice manufacturer 500 can make a profit by receiving orders formanufacturing devices.

Then an example of a sequence in which a production apparatusmanufacturer takes the initiative will be described. A productionapparatus manufacturer 700 commissions an inspection equipmentmanufacturer 600 to mount a compact foreign matter monitor 10 in aprocess processing apparatus P and pays for the mounting. Then, theprocess processing apparatus P in which the compact foreign mattermonitor 10 purchased from the inspection equipment manufacturer 600 ismounted is sold by the production apparatus manufacturer 700 to a devicemanufacturer 500 as a compact foreign matter monitor-integratedproduction apparatus. The device manufacturer 500 pays for theapparatus. The production apparatus manufacturer 700 collects a fixedamount of money (for a certain period) for the monitoring cost from thedevice manufacturer 500. Then, the production apparatus manufacturer 700is notified by the base system 20 of inspection results and, based onthe inspection results, performs failure analysis. As necessary, theproduction apparatus manufacturer 700 issues an alarm to the devicemanufacturer 500 and takes anti-dusting countermeasures to prevent massfailure.

Then, an example of a sequence in which a compact foreign matter monitor(optical head) is added will be described with reference to FIG. 40. Aninspection equipment manufacturer 600 leases one or plural compactforeign matter monitors 10 to a device manufacturer 500 and acquiresresults of foreign matter monitoring inspection from the base system 20of the device manufacturer 500 to grasp the dusting frequency. Ifnecessary, the inspection equipment manufacturer 600 leases anothercompact foreign matter monitor to the device manufacturer 500. Thisadded compact foreign matter monitor is used by the device manufacturer500 to locate the dusting source. The device manufacturer 500 pays tothe inspection equipment manufacturer 600 for the troubleshooting.

1. A system for monitoring foreign matter comprising: a manufacture linehaving plural process processing apparatuses; a production managementsystem which manages the processing of workpieces in the manufactureline; foreign matter monitors mounted as on-machine equipment in saidplural process processing apparatuses, said foreign matter monitors eachhaving: an optical head containing a detecting optical system forirradiating a workpiece with light and a detecting optical system forreceiving reflected and scattered light from the workpiece andconverting the received light to a detection image signal; and an A/Dconverter for converting the detection image signal, which is obtainedthrough conversion by the detecting optical system, to a detectiondigital image signal; and a base system having: a control unit foracquiring control information including information identifying eachforeign matter monitor, process processing information and workpieceinformation, the process processing information and the workpieceinformation being acquired from the production management system; abuffer memory for storing said detection digital image signal, which isacquired from each foreign matter monitor, in association with thecorresponding foreign matter monitor; a database storing inspectionrecipes each associated with a foreign matter monitor; and an imagesignal processing unit used for, based on a detection digital imagesignal associated with a foreign matter monitor and acquired from thebuffer memory, judging whether foreign matter and other defects arepresent on a workpiece according to an inspection recipe which isselected for the corresponding foreign matter monitor based on controlinformation from the control unit.
 2. A system for monitoring foreignmatter according to claim 1, wherein each of said plural main processprocessing apparatuses comprises: a process room to process workpieces;a cassette room where a cassette containing a workpiece is carried inand out; and a platform providing clean ambience to the workpiece fortransportation between the process room and the cassette room.
 3. Asystem for monitoring foreign matter according to claim 2, wherein anoptical head for the foreign matter monitor is set up in said platform.4. A system for monitoring foreign matter according to claim 1, whereineach of said plural main process processing apparatuses comprises: aprocess room to process workpieces; a cassette room where a cassettecontaining a workpiece is carried in and out; a platform providing cleanambience to the workpiece for transportation between the process roomand the cassette room; and a small clean environment room.
 5. A systemfor monitoring foreign matter according to claim 4, wherein an opticalhead for the foreign matter monitor is set up in said small cleanenvironment room.
 6. A system for monitoring foreign matter according toclaim 2, wherein said clean ambience is kept clean to class 20 orbetter.
 7. A system for monitoring foreign matter according to claim 4,wherein said clean ambience is kept clean to class 20 or better.
 8. Asystem for monitoring foreign matter according to claim 1, wherein saidimage signal processing unit in said base system is configured so as toprepare a defect distribution map over a workpiece for each foreignmatter monitor.
 9. A system for monitoring foreign matter according toclaim 1, wherein said base system further comprises a data analysisprocessing unit which performs failure analysis by comparing the defectoccurrence situation of a workpiece, judged by said image signalprocessing unit, with failure analysis reference data.
 10. A system formonitoring foreign matter according to claim 9, wherein results offailure analysis by said data analysis processing unit are displayed onan input/output terminal.
 11. A system for monitoring foreign matteraccording to claim 1, wherein the control unit in said base system has acapability of preparing inspection recipes associated respectively withforeign matter monitors.
 12. A system for monitoring foreign matteraccording to claim 1, wherein said image signal processing unit in saidbase system is configured so as to determine a defect distribution overa wafer for each foreign matter monitor.
 13. A system for monitoringforeign matter according to claim 1, wherein the control unit in saidbase system has a capability of preparing inspection recipes associatedrespectively with foreign matter monitors.
 14. A method of electroniccommerce, wherein the inspection equipment manufacturer whichmanufactures foreign matter monitors using a foreign matter monitoringsystem according to claim 1, demands payment via a communication networkto a chip device manufacturer for an economic effect by an increasedyield which is brought about as a result of anti-failure countermeasurestaken to an abnormal process processing apparatus located based ondefect occurrence information acquired from the base system.